Java Programming

for(i=0;i<i<files.length();i++)
{
 String excel=excelFiles[i]
 Date date=  new Date();
  int  rowCount= 45;
Sample samp=new Sample();
samp.createWorkbookForLogReport(excel,date,rowCount);
 }

    private HSSFWorkbook createWorkbookForLogReport(String excel,Date date,int rowCount) throws IOException {

        HSSFWorkbook wb = new HSSFWorkbook();
        HSSFSheet sheet = wb.createSheet("new sheet");

        int idx = 0; // rows index
        HSSFRow row = sheet.createRow((short)idx);
        idx++;
        String[] attributessss = 
        { "ExcelName", "Date and Time", "RowCount" };

        for (int j = 0; j < attributessss.length; j++) {
            attribute = attributessss[j];
            row.createCell((short)j).setCellValue((String)attribute);
        }

                 
            row = sheet.createRow((short)idx);
            row.createCell((short)0).setCellValue((String)excelFiles);
            row.createCell((short)1).setCellValue(date);
            row.createCell((short)2).setCellValue(rowCount);


            idx++;
     
        return wb;


    }


the parametres are continuously changing i am able to write once in the excel file.but couldnt able to append the same excel file.is there any possibility to append the single excel file for changing records.